Simple representation of quantum process tomography
Giuliano Benenti, G. Strini · Physical Review A · 2009
We show that the Fano representation leads to a particularly simple and appealing form of the quantum process tomography matrix ${\ensuremath{\chi}}_{F}$, in that the matrix ${\ensuremath{\chi}}_{F}$ is real, the number of matrix elements is exactly equal to the number of free parameters required for the complete characterization of a quantum operation, and these matrix elements are directly related to evolution of the expectation values of the system's polarization measurements. These facts are illustrated in the examples of one- and two-qubit quantum noise channels.